var cx = /[\u0000\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,
  escapable =
  /[\\\"\x00-\x1f\x7f-\x9f\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,
  gap,
  indent,
  meta = { // table of character substitutions
    '\b': '\\b',
    '\t': '\\t',
    '\n': '\\n',
    '\f': '\\f',
    '\r': '\\r',
    '"': '\\"',
    '\\': '\\\\'
  },
  rep;

function quote(string) {
  // If the string contains no control characters, no quote characters, and no
  // backslash characters, then we can safely slap some quotes around it.
  // Otherwise we must also replace the offending characters with safe escape
  // sequences.

  escapable.lastIndex = 0;
  return escapable.test(string) ? '"' + string.replace(escapable, function(a) {
    var c = meta[a];
    return typeof c === 'string' ? c :
      '\\u' + ('0000' + a.charCodeAt(0).toString(16)).slice(-4);
  }) + '"' : '"' + string + '"';
}

function str(key, holder) {
  // Produce a string from holder[key].
  var i, // The loop counter.
    k, // The member key.
    v, // The member value.
    length,
    mind = gap,
    partial,
    value = holder[key];

  // If the value has a toJSON method, call it to obtain a replacement value.
  if (value && typeof value === 'object' &&
    typeof value.toJSON === 'function') {
    value = value.toJSON(key);
  }

  // If we were called with a replacer function, then call the replacer to
  // obtain a replacement value.
  if (typeof rep === 'function') {
    value = rep.call(holder, key, value);
  }

  // What happens next depends on the value's type.
  switch (typeof value) {
    case 'string':
      return quote(value);

    case 'number':
      // JSON numbers must be finite. Encode non-finite numbers as null.
      return isFinite(value) ? String(value) : 'null';

    case 'boolean':
    case 'null':
      // If the value is a boolean or null, convert it to a string. Note:
      // typeof null does not produce 'null'. The case is included here in
      // the remote chance that this gets fixed someday.
      return String(value);

    case 'object':
      if (!value) return 'null';
      gap += indent;
      partial = [];

      // Array.isArray
      if (Object.prototype.toString.apply(value) === '[object Array]') {
        length = value.length;
        for (i = 0; i < length; i += 1) {
          partial[i] = str(i, value) || 'null';
        }

        // Join all of the elements together, separated with commas, and
        // wrap them in brackets.
        v = partial.length === 0 ? '[]' : gap ?
          '[\n' + gap + partial.join(',\n' + gap) + '\n' + mind + ']' :
          '[' + partial.join(',') + ']';
        gap = mind;
        return v;
      }

      // If the replacer is an array, use it to select the members to be
      // stringified.
      if (rep && typeof rep === 'object') {
        length = rep.length;
        for (i = 0; i < length; i += 1) {
          k = rep[i];
          if (typeof k === 'string') {
            v = str(k, value);
            if (v) {
              partial.push(quote(k) + (gap ? ': ' : ':') + v);
            }
          }
        }
      } else {
        // Otherwise, iterate through all of the keys in the object.
        for (k in value) {
          if (Object.prototype.hasOwnProperty.call(value, k)) {
            v = str(k, value);
            if (v) {
              partial.push(quote(k) + (gap ? ': ' : ':') + v);
            }
          }
        }
      }

      // Join all of the member texts together, separated with commas,
      // and wrap them in braces.

      v = partial.length === 0 ? '{}' : gap ?
        '{\n' + gap + partial.join(',\n' + gap) + '\n' + mind + '}' :
        '{' + partial.join(',') + '}';
      gap = mind;
      return v;
  }
}

module.exports = function(value, replacer, space) {
  var i;
  gap = '';
  indent = '';

  // If the space parameter is a number, make an indent string containing that
  // many spaces.
  if (typeof space === 'number') {
    for (i = 0; i < space; i += 1) {
      indent += ' ';
    }
  }
  // If the space parameter is a string, it will be used as the indent string.
  else if (typeof space === 'string') {
    indent = space;
  }

  // If there is a replacer, it must be a function or an array.
  // Otherwise, throw an error.
  rep = replacer;
  if (replacer && typeof replacer !== 'function' &&
    (typeof replacer !== 'object' || typeof replacer.length !== 'number')) {
    throw new Error('JSON.stringify');
  }

  // Make a fake root object containing our value under the key of ''.
  // Return the result of stringifying the value.
  return str('', {
    '': value
  });
};
